But is traffic “bad”? What sort of question is that you ask? Surely, the answer is 'yes', you say: time wasted stuck in traffic, the frustration, the needless idling of vehicles which creates both local (and global) pollution and so on. But let me suggest this: traffic congestion is also a sign of development. In fact, the more vibrant and dynamic the city as Nairobi surely is, the more traffic congestion you might expect...to paraphrase Gordon Gekko from the movie Wall Street, “Traffic is…good”!

To be clear from the onset: I will not oversimplify the unemployment (or inactivity) problem in the Western Balkan countries as solely due to a lack of skills in the population. Low employment rates result from both insufficient creation of jobs by enterprises and too-high a fraction of the workforce that is ill-equipped to take on the jobs that a modern economy creates. Both issues are intertwined. Solutions, therefore, require efforts on several fronts to enable a more vibrant private sector –including improvements in the business environment, enterprise restructuring, integration in global markets and promoting entrepreneurship— as well as to prepare workers for new job opportunities.

If you’re not already interested in livelihoods, you should be. Because livelihoods are the bottom line of development. Millions are spent on trying to build more effective states around the world, but development isn’t really about state capacity. At the end of those long causal chains and theories of change, there’s a person – an average Jo (sephine), a ‘little guy’. Making things work a little better for that person, making it easier for them to make their own choices and carve out a decent living…that is the why of development.

The economics book that has launched a thousand blog posts, Thomas Piketty’s Capital in the Twenty-First Country, tells a grand story of inequality past and present. One would expect that a book on global inequality would have much to say about development. However, the book has limited relevance for the developing world, and the empirical data he marshals for developing countries is weak.

Piketty’s central story is that convergence in the developed world and slower population growth will leave us with a permanently modest economic growth rate (g). Coupled with a constant return to wealth (r), concentration of capital ownership, and high rates of savings among the wealthy, the low g leads to rising wealth inequality over a longish run—something like the second half of the 20th century.

A low-g future for the developed world is a mostly uncontroversial assumption. (He assumes future GDP per capita growth of 1.2 percent for the U.S.) But Piketty draws conclusions for the world as a whole, and we are a long way from global convergence. As Branko Milanovic noted in his review, catch-up growth could fend off Piketty’s inequality dystopia for some time.

The new report of the International Comparison Program published last week promises to invigorate debate about the global economic landscape. In some areas, the report challenges conventional wisdom. In other areas, it reinforces the narrative.

The headline change according to The Economist is the rise of China to potentially become the largest economy in the world by the end of 2014. According to Angus Maddison, the United States’ economy became the largest in the world in 1872, and has remained the largest ever since. The new estimates suggest that China’s economy was less than 14% smaller than that of the US in 2011. Given that the Chinese economy is growing more than 5 percentage points faster than the US (7 percent versus 2 percent), it should overtake the US this year. This is considerably earlier than what most analysts had forecast. It will mark the first time in history that the largest economy in the world ranks so poorly in per capita terms. (China stands at a mere 99th place on this ranking.)

A puzzle: Sanitation is one of the most productive investments a government can make. There is now rigorous empirical evidence that improved sanitation systems reduce the incidence of diarrhea among children. Diarrhea, in turn, harms children’s nutritional status (by affecting their ability to retain nutrients). And inadequate nutrition (stunting, etc.) affects children’s cognitive skills, lifetime health and earnings. In short, the benefits of sanitation investment are huge. Cost-benefit analyses show rates of return of 17-55 percent, or benefit/cost ratios between 2 and 8.

But if the benefits are so high (relative to costs), why aren’t we seeing massive investments in sanitation? Why are there 470 million people in East Asia, 600 million in Africa and a billion people in South Asia lacking access to sanitation? Why are there more cellphones than toilets in Africa?